1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Common library for ADIS16XXX devices 4 * 5 * Copyright 2012 Analog Devices Inc. 6 * Author: Lars-Peter Clausen <lars@metafoo.de> 7 */ 8 9 #include <linux/delay.h> 10 #include <linux/gpio/consumer.h> 11 #include <linux/mutex.h> 12 #include <linux/device.h> 13 #include <linux/kernel.h> 14 #include <linux/spi/spi.h> 15 #include <linux/module.h> 16 #include <asm/unaligned.h> 17 18 #include <linux/iio/iio.h> 19 #include <linux/iio/imu/adis.h> 20 21 #define ADIS_MSC_CTRL_DATA_RDY_EN BIT(2) 22 #define ADIS_MSC_CTRL_DATA_RDY_POL_HIGH BIT(1) 23 #define ADIS_MSC_CTRL_DATA_RDY_DIO2 BIT(0) 24 #define ADIS_GLOB_CMD_SW_RESET BIT(7) 25 26 /** 27 * __adis_write_reg() - write N bytes to register (unlocked version) 28 * @adis: The adis device 29 * @reg: The address of the lower of the two registers 30 * @value: The value to write to device (up to 4 bytes) 31 * @size: The size of the @value (in bytes) 32 */ 33 int __adis_write_reg(struct adis *adis, unsigned int reg, unsigned int value, 34 unsigned int size) 35 { 36 unsigned int page = reg / ADIS_PAGE_SIZE; 37 int ret, i; 38 struct spi_message msg; 39 struct spi_transfer xfers[] = { 40 { 41 .tx_buf = adis->tx, 42 .bits_per_word = 8, 43 .len = 2, 44 .cs_change = 1, 45 .delay.value = adis->data->write_delay, 46 .delay.unit = SPI_DELAY_UNIT_USECS, 47 }, { 48 .tx_buf = adis->tx + 2, 49 .bits_per_word = 8, 50 .len = 2, 51 .cs_change = 1, 52 .delay.value = adis->data->write_delay, 53 .delay.unit = SPI_DELAY_UNIT_USECS, 54 }, { 55 .tx_buf = adis->tx + 4, 56 .bits_per_word = 8, 57 .len = 2, 58 .cs_change = 1, 59 .delay.value = adis->data->write_delay, 60 .delay.unit = SPI_DELAY_UNIT_USECS, 61 }, { 62 .tx_buf = adis->tx + 6, 63 .bits_per_word = 8, 64 .len = 2, 65 .delay.value = adis->data->write_delay, 66 .delay.unit = SPI_DELAY_UNIT_USECS, 67 }, { 68 .tx_buf = adis->tx + 8, 69 .bits_per_word = 8, 70 .len = 2, 71 .delay.value = adis->data->write_delay, 72 .delay.unit = SPI_DELAY_UNIT_USECS, 73 }, 74 }; 75 76 spi_message_init(&msg); 77 78 if (adis->current_page != page) { 79 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); 80 adis->tx[1] = page; 81 spi_message_add_tail(&xfers[0], &msg); 82 } 83 84 switch (size) { 85 case 4: 86 adis->tx[8] = ADIS_WRITE_REG(reg + 3); 87 adis->tx[9] = (value >> 24) & 0xff; 88 adis->tx[6] = ADIS_WRITE_REG(reg + 2); 89 adis->tx[7] = (value >> 16) & 0xff; 90 fallthrough; 91 case 2: 92 adis->tx[4] = ADIS_WRITE_REG(reg + 1); 93 adis->tx[5] = (value >> 8) & 0xff; 94 fallthrough; 95 case 1: 96 adis->tx[2] = ADIS_WRITE_REG(reg); 97 adis->tx[3] = value & 0xff; 98 break; 99 default: 100 return -EINVAL; 101 } 102 103 xfers[size].cs_change = 0; 104 105 for (i = 1; i <= size; i++) 106 spi_message_add_tail(&xfers[i], &msg); 107 108 ret = spi_sync(adis->spi, &msg); 109 if (ret) { 110 dev_err(&adis->spi->dev, "Failed to write register 0x%02X: %d\n", 111 reg, ret); 112 } else { 113 adis->current_page = page; 114 } 115 116 return ret; 117 } 118 EXPORT_SYMBOL_NS_GPL(__adis_write_reg, IIO_ADISLIB); 119 120 /** 121 * __adis_read_reg() - read N bytes from register (unlocked version) 122 * @adis: The adis device 123 * @reg: The address of the lower of the two registers 124 * @val: The value read back from the device 125 * @size: The size of the @val buffer 126 */ 127 int __adis_read_reg(struct adis *adis, unsigned int reg, unsigned int *val, 128 unsigned int size) 129 { 130 unsigned int page = reg / ADIS_PAGE_SIZE; 131 struct spi_message msg; 132 int ret; 133 struct spi_transfer xfers[] = { 134 { 135 .tx_buf = adis->tx, 136 .bits_per_word = 8, 137 .len = 2, 138 .cs_change = 1, 139 .delay.value = adis->data->write_delay, 140 .delay.unit = SPI_DELAY_UNIT_USECS, 141 }, { 142 .tx_buf = adis->tx + 2, 143 .bits_per_word = 8, 144 .len = 2, 145 .cs_change = 1, 146 .delay.value = adis->data->read_delay, 147 .delay.unit = SPI_DELAY_UNIT_USECS, 148 }, { 149 .tx_buf = adis->tx + 4, 150 .rx_buf = adis->rx, 151 .bits_per_word = 8, 152 .len = 2, 153 .cs_change = 1, 154 .delay.value = adis->data->read_delay, 155 .delay.unit = SPI_DELAY_UNIT_USECS, 156 }, { 157 .rx_buf = adis->rx + 2, 158 .bits_per_word = 8, 159 .len = 2, 160 .delay.value = adis->data->read_delay, 161 .delay.unit = SPI_DELAY_UNIT_USECS, 162 }, 163 }; 164 165 spi_message_init(&msg); 166 167 if (adis->current_page != page) { 168 adis->tx[0] = ADIS_WRITE_REG(ADIS_REG_PAGE_ID); 169 adis->tx[1] = page; 170 spi_message_add_tail(&xfers[0], &msg); 171 } 172 173 switch (size) { 174 case 4: 175 adis->tx[2] = ADIS_READ_REG(reg + 2); 176 adis->tx[3] = 0; 177 spi_message_add_tail(&xfers[1], &msg); 178 fallthrough; 179 case 2: 180 adis->tx[4] = ADIS_READ_REG(reg); 181 adis->tx[5] = 0; 182 spi_message_add_tail(&xfers[2], &msg); 183 spi_message_add_tail(&xfers[3], &msg); 184 break; 185 default: 186 return -EINVAL; 187 } 188 189 ret = spi_sync(adis->spi, &msg); 190 if (ret) { 191 dev_err(&adis->spi->dev, "Failed to read register 0x%02X: %d\n", 192 reg, ret); 193 return ret; 194 } 195 196 adis->current_page = page; 197 198 switch (size) { 199 case 4: 200 *val = get_unaligned_be32(adis->rx); 201 break; 202 case 2: 203 *val = get_unaligned_be16(adis->rx + 2); 204 break; 205 } 206 207 return ret; 208 } 209 EXPORT_SYMBOL_NS_GPL(__adis_read_reg, IIO_ADISLIB); 210 /** 211 * __adis_update_bits_base() - ADIS Update bits function - Unlocked version 212 * @adis: The adis device 213 * @reg: The address of the lower of the two registers 214 * @mask: Bitmask to change 215 * @val: Value to be written 216 * @size: Size of the register to update 217 * 218 * Updates the desired bits of @reg in accordance with @mask and @val. 219 */ 220 int __adis_update_bits_base(struct adis *adis, unsigned int reg, const u32 mask, 221 const u32 val, u8 size) 222 { 223 int ret; 224 u32 __val; 225 226 ret = __adis_read_reg(adis, reg, &__val, size); 227 if (ret) 228 return ret; 229 230 __val = (__val & ~mask) | (val & mask); 231 232 return __adis_write_reg(adis, reg, __val, size); 233 } 234 EXPORT_SYMBOL_NS_GPL(__adis_update_bits_base, IIO_ADISLIB); 235 236 #ifdef CONFIG_DEBUG_FS 237 238 int adis_debugfs_reg_access(struct iio_dev *indio_dev, unsigned int reg, 239 unsigned int writeval, unsigned int *readval) 240 { 241 struct adis *adis = iio_device_get_drvdata(indio_dev); 242 243 if (readval) { 244 u16 val16; 245 int ret; 246 247 ret = adis_read_reg_16(adis, reg, &val16); 248 if (ret == 0) 249 *readval = val16; 250 251 return ret; 252 } 253 254 return adis_write_reg_16(adis, reg, writeval); 255 } 256 EXPORT_SYMBOL_NS(adis_debugfs_reg_access, IIO_ADISLIB); 257 258 #endif 259 260 /** 261 * __adis_enable_irq() - Enable or disable data ready IRQ (unlocked) 262 * @adis: The adis device 263 * @enable: Whether to enable the IRQ 264 * 265 * Returns 0 on success, negative error code otherwise 266 */ 267 int __adis_enable_irq(struct adis *adis, bool enable) 268 { 269 int ret; 270 u16 msc; 271 272 if (adis->data->enable_irq) 273 return adis->data->enable_irq(adis, enable); 274 275 if (adis->data->unmasked_drdy) { 276 if (enable) 277 enable_irq(adis->spi->irq); 278 else 279 disable_irq(adis->spi->irq); 280 281 return 0; 282 } 283 284 ret = __adis_read_reg_16(adis, adis->data->msc_ctrl_reg, &msc); 285 if (ret) 286 return ret; 287 288 msc |= ADIS_MSC_CTRL_DATA_RDY_POL_HIGH; 289 msc &= ~ADIS_MSC_CTRL_DATA_RDY_DIO2; 290 if (enable) 291 msc |= ADIS_MSC_CTRL_DATA_RDY_EN; 292 else 293 msc &= ~ADIS_MSC_CTRL_DATA_RDY_EN; 294 295 return __adis_write_reg_16(adis, adis->data->msc_ctrl_reg, msc); 296 } 297 EXPORT_SYMBOL_NS(__adis_enable_irq, IIO_ADISLIB); 298 299 /** 300 * __adis_check_status() - Check the device for error conditions (unlocked) 301 * @adis: The adis device 302 * 303 * Returns 0 on success, a negative error code otherwise 304 */ 305 int __adis_check_status(struct adis *adis) 306 { 307 u16 status; 308 int ret; 309 int i; 310 311 ret = __adis_read_reg_16(adis, adis->data->diag_stat_reg, &status); 312 if (ret) 313 return ret; 314 315 status &= adis->data->status_error_mask; 316 317 if (status == 0) 318 return 0; 319 320 for (i = 0; i < 16; ++i) { 321 if (status & BIT(i)) { 322 dev_err(&adis->spi->dev, "%s.\n", 323 adis->data->status_error_msgs[i]); 324 } 325 } 326 327 return -EIO; 328 } 329 EXPORT_SYMBOL_NS_GPL(__adis_check_status, IIO_ADISLIB); 330 331 /** 332 * __adis_reset() - Reset the device (unlocked version) 333 * @adis: The adis device 334 * 335 * Returns 0 on success, a negative error code otherwise 336 */ 337 int __adis_reset(struct adis *adis) 338 { 339 int ret; 340 const struct adis_timeout *timeouts = adis->data->timeouts; 341 342 ret = __adis_write_reg_8(adis, adis->data->glob_cmd_reg, 343 ADIS_GLOB_CMD_SW_RESET); 344 if (ret) { 345 dev_err(&adis->spi->dev, "Failed to reset device: %d\n", ret); 346 return ret; 347 } 348 349 msleep(timeouts->sw_reset_ms); 350 351 return 0; 352 } 353 EXPORT_SYMBOL_NS_GPL(__adis_reset, IIO_ADIS_LIB); 354 355 static int adis_self_test(struct adis *adis) 356 { 357 int ret; 358 const struct adis_timeout *timeouts = adis->data->timeouts; 359 360 ret = __adis_write_reg_16(adis, adis->data->self_test_reg, 361 adis->data->self_test_mask); 362 if (ret) { 363 dev_err(&adis->spi->dev, "Failed to initiate self test: %d\n", 364 ret); 365 return ret; 366 } 367 368 msleep(timeouts->self_test_ms); 369 370 ret = __adis_check_status(adis); 371 372 if (adis->data->self_test_no_autoclear) 373 __adis_write_reg_16(adis, adis->data->self_test_reg, 0x00); 374 375 return ret; 376 } 377 378 /** 379 * __adis_initial_startup() - Device initial setup 380 * @adis: The adis device 381 * 382 * The function performs a HW reset via a reset pin that should be specified 383 * via GPIOLIB. If no pin is configured a SW reset will be performed. 384 * The RST pin for the ADIS devices should be configured as ACTIVE_LOW. 385 * 386 * After the self-test operation is performed, the function will also check 387 * that the product ID is as expected. This assumes that drivers providing 388 * 'prod_id_reg' will also provide the 'prod_id'. 389 * 390 * Returns 0 if the device is operational, a negative error code otherwise. 391 * 392 * This function should be called early on in the device initialization sequence 393 * to ensure that the device is in a sane and known state and that it is usable. 394 */ 395 int __adis_initial_startup(struct adis *adis) 396 { 397 const struct adis_timeout *timeouts = adis->data->timeouts; 398 struct gpio_desc *gpio; 399 u16 prod_id; 400 int ret; 401 402 /* check if the device has rst pin low */ 403 gpio = devm_gpiod_get_optional(&adis->spi->dev, "reset", GPIOD_OUT_HIGH); 404 if (IS_ERR(gpio)) 405 return PTR_ERR(gpio); 406 407 if (gpio) { 408 usleep_range(10, 12); 409 /* bring device out of reset */ 410 gpiod_set_value_cansleep(gpio, 0); 411 msleep(timeouts->reset_ms); 412 } else { 413 ret = __adis_reset(adis); 414 if (ret) 415 return ret; 416 } 417 418 ret = adis_self_test(adis); 419 if (ret) 420 return ret; 421 422 /* 423 * don't bother calling this if we can't unmask the IRQ as in this case 424 * the IRQ is most likely not yet requested and we will request it 425 * with 'IRQF_NO_AUTOEN' anyways. 426 */ 427 if (!adis->data->unmasked_drdy) 428 __adis_enable_irq(adis, false); 429 430 if (!adis->data->prod_id_reg) 431 return 0; 432 433 ret = adis_read_reg_16(adis, adis->data->prod_id_reg, &prod_id); 434 if (ret) 435 return ret; 436 437 if (prod_id != adis->data->prod_id) 438 dev_warn(&adis->spi->dev, 439 "Device ID(%u) and product ID(%u) do not match.\n", 440 adis->data->prod_id, prod_id); 441 442 return 0; 443 } 444 EXPORT_SYMBOL_NS_GPL(__adis_initial_startup, IIO_ADISLIB); 445 446 /** 447 * adis_single_conversion() - Performs a single sample conversion 448 * @indio_dev: The IIO device 449 * @chan: The IIO channel 450 * @error_mask: Mask for the error bit 451 * @val: Result of the conversion 452 * 453 * Returns IIO_VAL_INT on success, a negative error code otherwise. 454 * 455 * The function performs a single conversion on a given channel and post 456 * processes the value accordingly to the channel spec. If a error_mask is given 457 * the function will check if the mask is set in the returned raw value. If it 458 * is set the function will perform a self-check. If the device does not report 459 * a error bit in the channels raw value set error_mask to 0. 460 */ 461 int adis_single_conversion(struct iio_dev *indio_dev, 462 const struct iio_chan_spec *chan, 463 unsigned int error_mask, int *val) 464 { 465 struct adis *adis = iio_device_get_drvdata(indio_dev); 466 unsigned int uval; 467 int ret; 468 469 mutex_lock(&adis->state_lock); 470 471 ret = __adis_read_reg(adis, chan->address, &uval, 472 chan->scan_type.storagebits / 8); 473 if (ret) 474 goto err_unlock; 475 476 if (uval & error_mask) { 477 ret = __adis_check_status(adis); 478 if (ret) 479 goto err_unlock; 480 } 481 482 if (chan->scan_type.sign == 's') 483 *val = sign_extend32(uval, chan->scan_type.realbits - 1); 484 else 485 *val = uval & ((1 << chan->scan_type.realbits) - 1); 486 487 ret = IIO_VAL_INT; 488 err_unlock: 489 mutex_unlock(&adis->state_lock); 490 return ret; 491 } 492 EXPORT_SYMBOL_NS_GPL(adis_single_conversion, IIO_ADISLIB); 493 494 /** 495 * adis_init() - Initialize adis device structure 496 * @adis: The adis device 497 * @indio_dev: The iio device 498 * @spi: The spi device 499 * @data: Chip specific data 500 * 501 * Returns 0 on success, a negative error code otherwise. 502 * 503 * This function must be called, before any other adis helper function may be 504 * called. 505 */ 506 int adis_init(struct adis *adis, struct iio_dev *indio_dev, 507 struct spi_device *spi, const struct adis_data *data) 508 { 509 if (!data || !data->timeouts) { 510 dev_err(&spi->dev, "No config data or timeouts not defined!\n"); 511 return -EINVAL; 512 } 513 514 mutex_init(&adis->state_lock); 515 516 if (!spi->cs_inactive.value) { 517 spi->cs_inactive.value = data->cs_change_delay; 518 spi->cs_inactive.unit = SPI_DELAY_UNIT_USECS; 519 } 520 521 adis->spi = spi; 522 adis->data = data; 523 iio_device_set_drvdata(indio_dev, adis); 524 525 if (data->has_paging) { 526 /* Need to set the page before first read/write */ 527 adis->current_page = -1; 528 } else { 529 /* Page will always be 0 */ 530 adis->current_page = 0; 531 } 532 533 return 0; 534 } 535 EXPORT_SYMBOL_NS_GPL(adis_init, IIO_ADISLIB); 536 537 MODULE_LICENSE("GPL"); 538 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 539 MODULE_DESCRIPTION("Common library code for ADIS16XXX devices"); 540